Health

Hepatosplenic candidiasis in children with acute leukemia

Article Abstract:

Immunosuppression is a serious side effect of chemotherapy which exposes the patient to significant complications from infection. Fungal infections are among the more serious potential infections, and candidiasis is the most common. In the last few years, microabscesses in the liver and spleen have been reported in increasing frequency. In a series of 60 children treated with intensive chemotherapy for acute lymphoblastic leukemia, systemic candidiasis was observed in seven. Of those, three children were diagnosed with hepatosplenic (liver and spleen) candidiasis. The patients developed a prolonged fever, and the neutrophils (type of white blood cell) in the blood were seriously reduced in number. However, the children did not have the toxic appearance normally associated with systemic infection. Blood cultures were negative, but colonies of candida albicans were evident in the patients' throat or in stool samples. A computerized tomography (CT) scan (diagnostic imaging technique) was performed on two patients, and numerous low-density lesions were visible; lesions were also observed using ultrasonography. The patients were treated with amphotericin B and 5-fluorocytosine. After two months, the 5-fluorocytosine was discontinued. One patient, for whom antifungal treatment was delayed, died before the infection was controlled. The other two patients are alive; one is in complete remission and the other is cured. These cases point out the need to be aware of the possibility of systemic candidiasis in these patients. Blood cultures are often negative and the small lesions do not appear on CT scan images or ultrasonograms until after the neutrophil count returns to normal. Successful treatment may depend on the initiation of therapy as soon as candidiasis is suspected. (Consumer Summary produced by Reliance Medical Information, Inc.)

Influence of chemotherapeutic agents on superoxide anion production by polymorphonuclear leukocytes

Article Abstract:

One of the most common side effects of anticancer drugs is the suppression of the immune system, which may lead to infection as a serious complication of treatment. A great deal of research has explored the effect of chemotherapeutic agents on polymorphonuclear leukocytes (PMNLs), phagocytic white blood cells which can eat and destroy bacteria. Much of the research has been contradictory, however, and few conclusions have been drawn. Since the ability of PMNLs to kill bacteria in an experimental assay may be affected by many laboratory conditions, an attempt was made to examine a fundamental characteristic of the cells that is critical to their ability to destroy bacteria. Polymorphonuclear cells generate quantities of the superoxide anion, which is an oxygen molecule with an added negative charge. This ion is highly reactive chemically and can literally ''burn'' the proteins and other constituents of a target organism. Eleven chemotherapeutic drugs were incubated with PMNLs prior to the assay of the ability to produce superoxide. Only predonine did not suppress superoxide production. The remainder, which included commonly used anticancer agents cisplatin, doxorubicin, 5-fluorouracil, and etoposide, suppressed superoxide production, and may thus exert a similar effect when administered to patients. Curiously, the suppressive effects of cisplatin were reduced when the cells were incubated in the drug for a longer time; there is no obvious explanation for this phenomenon. While it is not known in what way chemotherapeutic drugs might influence the production of superoxide anions, the phenomenon must be considered as a possible mechanism for the increased susceptibility to infection observed among patients undergoing chemotherapy. (Consumer Summary produced by Reliance Medical Information, Inc.)

The effects of different cumulative doses of chemotherapy on testicular function: results in 75 patients treated for Hodgkin's disease during childhood or adolescence

Article Abstract:

Improvements in chemotherapy have resulted in better survival rates for patients with Hodgkin's disease. Some pediatric studies have indicated a 5-year event-free survival rate of 96 percent. However, evidence is accumulating that there may be some damage to the organs, including organs of the hypothalamic-pituitary-testicular system. In an investigation of 75 boys treated for Hodgkin's disease with radiation and chemotherapy, abnormalities attributed to testicular damage were found. Four patients were without sperm cells, although development during puberty was normal in these patients, as were levels of testosterone. However, 24 percent had elevated basal levels of luteinizing hormone (LH), which suggests possible damage to the Leydig cells, the interstitial cells of the testes which manufacture testosterone. In addition, the experimental injection of gonadotrophin releasing hormone and thyroid stimulating hormone releasing hormone revealed an elevated LH level in a full 87.8 percent of the patients. Similarly, the basal level of follicle stimulating hormone (FSH) and the level stimulated by releasing factor injection were elevated in 40.5 and 53.4 percent of the patients, respectively. The testicular damage seemed unrelated to the age at which the boy received the chemotherapy, but the incidence of both basal and stimulated hormone levels was greater among those boys who received higher doses of chemotherapy. The drug procarbazine seemed to be especially associated with testicular damage, but the sample of patients is too small to ascribe the major toxic role to this agent. (Consumer Summary produced by Reliance Medical Information, Inc.)